Madeleine Joan Blaustein, who was also credited as Addie Blaustein early in her voice acting career, was an American voice actress known for her extensive work with 4Kids Entertainment, DuArt Film and Video, and NYAV Post. Born on October 9, 1960, in Long Island, New York, she built a diverse career that spanned voice acting, comic book writing, and creative direction before her passing on December 11, 2008.

Before becoming a prominent voice in animation, Blaustein had a significant career in comics. In the late 1980s and early 1990s, she worked for Marvel Comics and DC Comics as an editor and writer. She later joined Milestone Media as a production manager and writer, where she co-created storylines for titles such as Hardware and Static. During her time at Milestone, she co-wrote the miniseries Deathwish, which featured one of mainstream superhero comics' first transgender characters. Following her comic book career, she also served as the Creative Director for the Weekly World News.

Blaustein’s voice acting career was defined by a remarkable vocal range, allowing her to portray a wide variety of characters, from tough and deep-voiced men to more whimsical creatures. She began voicing characters for the English dub of the Pokémon anime, initially providing filler voices before taking over the role of Meowth from episode 31. She would go on to voice the iconic talking Pokémon through the show's eighth season. Her portrayal of Meowth extended into numerous Pokémon films and specials, including Pokémon: The First Movie, Pokémon 4Ever, Pokémon Heroes, Pokémon: Jirachi Wish Maker, and the specials Pikachu's Rescue Adventure and Pikachu and Pichu. Her work on the franchise made her a beloved figure among fans.

Beyond Pokémon, Blaustein was a regular presence in many English-dubbed anime series produced by 4Kids. She voiced Oslo in Fighting Foodons, Chef Kawasaki and Waddle Doo in Kirby: Right Back at Ya!, and Dr. Kureha in the 4Kids dub of One Piece. She was also a staple in the Yu-Gi-Oh! franchise, providing the voice of Solomon Muto (Yugi's grandfather) in the original series and Sartorius in Yu-Gi-Oh! GX. Her talent extended to video games as well, with memorable performances as Arngrim, Lawfer, and Lezard Valeth in Valkyrie Profile, and as E-123 Omega in the Sonic the Hedgehog series.